This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 15 |
| 6 | 50 |
| 7 | 181 |
| 8 | 698 |
| 9 | 2837 |
| 10 | 12062 |
| 11 | 53374 |
| 12 | 244923 |
| 13 | 1162536 |
| 14 | 5697119 |
| 15 | 28786266 |
| 16 | 149814059 |
| 17 | 802436166 |
| 18 | 4420515689 |
| 19 | 25031466730 |
| 20 | 145616087486 |
| 21 | 869760092469 |
| 22 | 5330945435272 |
| 23 | 33508699787635 |
| 24 | 215863606818041 |